# SeaKey vs Emerald Books

The clearest difference is rating: SeaKey at 5.0 against Emerald Books's 1.0. SeaKey also leads on iOS requirement (13.0 vs 16.0). Emerald Books's advantage is update cadence (fortnightly vs every 8 months) and ratings volume (5 vs 1). On price, ads, in-app purchases and monetization model there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

SeaKey holds the better App Store score, 5.0 against 1.0. That said, the two scores are not equally well evidenced: Emerald Books has 5 ratings behind it against 1, so its average is the more settled of the two.

SeaKey ships an update every 8 months, Emerald Books fortnightly. The most recent releases landed on October 15, 2026 and October 18, 2026 respectively.

## The numbers

| Metric | SeaKey | Emerald Books |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/seakey/id6448617545/reviews)** | [1.0 (5 ratings)](https://appshunter.io/ios/app/emerald-books/id6498716688/reviews) |
| Number of ratings | 1 | **5** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 8 months | **Fortnightly** |
| Monetization | Free | Free |
| Size | 87 MB | 34 MB |
| Requires iOS | **13.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Code for Nature](https://appshunter.io/developer/1829374322) | [Glassboxx Limited](https://appshunter.io/developer/1547970169) |

## What reviewers say

### SeaKey

[App page](https://appshunter.io/ios/app/seakey/id6448617545)

This toolbox helps identify seaweeds found in the German North Sea. It features an interactive key for species identification and detailed taxon profiles for verification. A glossary is also included to explain scientific terms.

**Highlights:** Interactive Identification Key, Species identification, Taxon Profiles, Glossary of scientific terms, German North Sea focus

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Emerald Books

[App page](https://appshunter.io/ios/app/emerald-books/id6498716688)

Access your purchased ebooks and audiobooks securely and conveniently. Enjoy features like bookmarking, customizable reading settings, and background playback for audio content. Download your library for offline enjoyment.

**Highlights:** Secure access to purchased ebooks, Offline reading and listening, Customizable reading experience, Audiobook playback with sleep timer, Cross-device bookmarking, Full text search

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is SeaKey free?

SeaKey is free to download, with no in-app purchases.

### Is Emerald Books free?

Emerald Books is free to download, with no in-app purchases.

### Which has better reviews, SeaKey or Emerald Books?

SeaKey is rated higher. SeaKey averages 5.0 out of 5 from 1 ratings, while Emerald Books averages 1.0 from 5 ratings.

### Do SeaKey or Emerald Books have ads?

Neither SeaKey nor Emerald Books shows ads.

### Which is updated more often, SeaKey or Emerald Books?

SeaKey ships an update every 8 months, and Emerald Books fortnightly. Most recently, SeaKey was updated on October 15, 2026 and Emerald Books on October 18, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*